Fair Value Disclosures - Assets Measured at Fair Value on Non-recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other real estate owned	$ 279	$ 7,400
Total assets	48	187
Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed loans held for investment	33,118	30,900
Other real estate owned	279	7,355
Total assets	33,397	38,255
Fair Value, Nonrecurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed loans held for investment	0	0
Other real estate owned	0	0
Total assets	0	0
Fair Value, Nonrecurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed loans held for investment	0	0
Other real estate owned	0	0
Total assets	0	0
Fair Value, Nonrecurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed loans held for investment	33,118	30,900
Other real estate owned	279	7,355
Total assets	$ 33,397	$ 38,255